# CVE-2026-99257: Linux kernel GPIO null pointer dereference in shared GPIO lookup

Source: https://junglewise.ai/threats/cve-2026-99257-in-the-linux-kernel-the-following-vulnerability-has-been-resolved  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-03. Updated: 2026-11-03  
License: CC BY 4.0 with a link back

CVE-2026-99257 · Severity: info · Published 2026-11-03

A Linux kernel bug could cause a system crash when certain GPIO lookup operations are performed without a device reference. This is a stability issue that prevents the kernel from running properly in specific hardware configurations, but does not allow attackers to gain unauthorized access or data.

Technologies: [Unknown Linux kernel](https://junglewise.ai/threats/technologies/unknown-linux-kernel). Vendors: [Unknown](https://junglewise.ai/threats/vendors/unknown).

## Quick answers

**Is CVE-2026-99257 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-99257 being exploited in the wild.

**How severe is CVE-2026-99257?** Informational severity, published 3 November 2026.

**Which products and versions are affected?** Unknown Linux kernel All versions from introduction of shared GPIO support (commit a060b8c511ab) prior to this fix.

**Is there a fix for CVE-2026-99257?** A patch was published on 2026-10-15: Original fix commit cf73c3fc03c43a8a86fd487c62390b4744eff9ec Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-99257 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-2026-99257?** Check whether you run Unknown Linux kernel at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A null pointer dereference occurs in the GPIO shared library when gpio_shared_add_proxy_lookup() is called with a NULL consumer device pointer during fwnode-based GPIO lookup. The vulnerability is in drivers/gpio/gpiolib-shared.c where dev_name(consumer) was dereferenced without checking if consumer was NULL. The fix adds a bounds check that returns -EOPNOTSUPP if consumer is NULL, gracefully handling this unsupported scenario.

## Affected products

- <UNKNOWN> Linux kernel All versions from introduction of shared GPIO support (commit a060b8c511ab) prior to this fix

## Timeline

- 2026-11-03: disclosed
- 2026-10-15: patched: Original fix commit cf73c3fc03c43a8a86fd487c62390b4744eff9ec
- 2026-11-03: advisory

## References

- [https://git.kernel.org/stable/c/7f9eb6aaf9a3ab7fa2b7dcc38660c27db12d4ec1](https://git.kernel.org/stable/c/7f9eb6aaf9a3ab7fa2b7dcc38660c27db12d4ec1)
- [https://git.kernel.org/stable/c/cf73c3fc03c43a8a86fd487c62390b4744eff9ec](https://git.kernel.org/stable/c/cf73c3fc03c43a8a86fd487c62390b4744eff9ec)

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